Signal power measurement is a commonly performed test in radio frequency (RF) test and measurement. A variety of measurement systems provide some form of power measurement including, but not limited to, power meters, spectrum analyzers, scalar network analyzers, and vector network analyzers. Power meters are generally considered a preferred measurement tool for performing precise and accurate power measurements. A vector network analyzer (VNA) can also provide accurate power measurements of a signal emitted by a device under test (DUT) provided the VNA is properly calibrated. In particular, error coefficients from a full two-port calibration of the VNA may be used to compute a correction of raw power measurements taken using the VNA to yield accurate power measurements. See for example, Shoulders et al., U.S. Pat. No. 7,061,254, incorporated herein by reference.
However, in some situations a full two-port calibration is either difficult to perform or is not needed for other reasons and therefore is not performed. For example, when making waveguide mixer scalar conversion gain measurements, performing a full two-port calibration of a VNA can be problematic due to the frequency conversion inherent in the operation of the mixer. In other situations, a full two-port calibration of the VNA (or multiport calibration of a multiport VNA) is simply too complicated to be practical. In such situations where a full two-port or full multiport calibration is not desirable or is simply not performed, the accuracy of the VNA-based power measurement will suffer from a presence of systematic errors associated with the measurement process.